This invention relates to devices for positioning an end portion of a supply roll of heat sealable film over the open end of a cup or similar shaped container, moving the cup and film end portion into engagement, heat fusing the film to the lip of the cup, and cutting the fused film end portion from the supply roll.
U.S. Pat. Nos. 3,286,437 and 3,501,896 describe such devices in which the supply roll of film is rotatably mounted on the device, and the means for advancing an end portion engages the film adjacent the supply roll and pushes an end portion of the film over the application station from whence the end portion is heat sealed to the lip of a cup and severed from the roll. Since the film is pushed to the application station over the cup, the device provides no assurance that wrinkles will not be induced into flexible film, which wrinkles could result in an improper seal between the film and the cup.